The invention relates to a method of modifying a first binary word, comprising a plurality of bits which represent the value of a first analog signal, in order to produce a second binary word, whose bits represent the value of a second analog signal, said last-mentioned value being in a predetermined ratio to the value of the first analog signal.
The invention further relates to a device for carrying out the method mentioned in the opening paragraph. Such a method is known from the article "A digital attenuator with 1 dB steps" in the Hewlett Packard Journal of January 1980, page 10. This article describes a method of attenuating pulse-modulated signals, which method can be carried out by means of a digital attenuator comprising two registers and an adder and is controlled by a suitable logic circuit. The known method is suitable for attenuating or amplifying a pulse-code modulated signal in 1 dB steps and is eminently suited for use in digitized measuring equipment. The known method provides an accurate attenuation or amplification but is so complex, that it is less suitable for use in simple signal processing equipment, such as playback equipment and receivers, where a smaller accuracy is needed and where it is important to achieve the desired result by simpler means.